For those thinking of trying this: iMac with Thunderbolt 1 used an Apple TB3 to TB2 Adapter with Cellularize USB-C Female Adapter to connect this StarTech USB hub and it didn't work . Also does not work with Macbook Pro with TB2 ports (2015). I chose this hub and the Cellularize adapter because they are both Thunderbolt 3 compatible, which is required to use the Thunderbolt ports. The device must be compatible with Thunderbolt. In theory, the setup I chose should have worked. I have no idea which link in the adapter chain failed. I read that the Cellularize adapter needs to be oriented a certain way, so I reoriented it every which way I could think of and it just didn't work. works as a TB3 to TB2 adapter and also as a TB2 to TB3 adapter if the devices are Thunderbolt compatible. Of course, you're limited by your port limits to 10 Gbps (TB1) or 20 Gbps (TB2), as well as the lower available performance for older ports. I really don't understand why there are no such hubs that work with TB1 or TB2. There's an adapter that gives you a USB port and an Ethernet port (or HDMI, depending on the adapter model) for $80, as well as a hub with one or two of the most popular ports, but that costs a few hundred bucks or so more. But nothing in between. It's weird that older devices aren't supported. My computers still work!
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